Definition

PET scans use a radioactive tracer that is introduced into your body to measure the cellular activity of the cell type or body part being scanned. A CT scan takes a large number of x-rays. These are analyzed by a computer to create a 3-dimensional image of the body part being studied. When both tests are performed at the same time, the information about function and structure is integrated through computer models.

Because PET/CT scans provide a combination of information about the function and structure of a body part, they are useful for the early diagnosis of cancer. Not only can an abnormal tumor be seen, but the function of the cells that make up the tumor can be analyzed as well. This can help to differentiate between cancerous and noncancerous growths.
PET/CT can also be used to see if cancer has spread into other areas of the body.

Brain, endocrine, and heart disorders are also studied using PET/CT scans.

Prior to Test

Prepare a list of medications you are taking and bring the list with you to the test. If you have
diabetes, discuss taking your diabetic medications and/or insulin with your doctor prior to the test. An abnormal blood glucose level may interfere with the tests results.

Let your doctor know if you have kidney disease. The doctor may need to take steps to avoid kidney injury during the test.

To prepare for your test, you may need to do the following several hours in advance:

Not eat anything after a certain time

Avoid beverages with high sugar and calorie content

Drink plenty of water

If you are breastfeeding, talk to your doctor before you go for your test. Your doctor may recommend that you pump breast milk ahead of time and use it until the contrast materials are no longer in your body.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

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